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Electric brain potentials evoked by pictures of faces and non-faces: a search for "face-specific" EEG-potentials.

In three different experimental series, electroencephalographic responses evoked by changes in pictorial patterns were recorded in 29 adult human subjects (19 females, 10 males). Quantitative data evaluation for the evoked responses from electrodes T5, T6, Cz, Pz (10-20 system) was performed. The stimuli were projected to a 4 x 6 degree binocularly viewed field. The patterns changed within 6 ms every 2.5-4.5 s according to a random program. Paradigm (1): Identical line drawings of a face, a tree and a chair were used, either black on white (P-stimuli) or white on black (N-stimuli); in each set altogether 160 slides appeared in semi-random order. At Cz and Pz a prototypical EEG-response evoked by face stimuli was found exhibiting 3 prominent peaks, very similar for P-stimuli and N-stimuli. A P150 maximum was especially pronounced in the responses to face stimuli but absent in the evoked potentials aroused by chair or tree stimuli. The difference curves (face-chair, face-tree, chair-tree) supported the hypothesis of "face-responsive" components in these responses. Paradigm (2): 4 x 6 degree slides (black and white photographs) of 54 different human faces, 53 different vases and 53 different pairs of shoes were projected as in paradigm (1), but instruction to the subjects on a supposed post-test memory task raised their attention during the recordings. "Face-responsive" components (an early N 140-160, P 210-240, N 300) were more marked in female than in male subjects, and again most pronounced at electrode Cz. Paradigm (3): When a recognition task was included in paradigm (2)--9 out of 192 items were memorized 20 minutes before the recording session--essentially the same evoked potentials were obtained as in (2), but an additional late positive wave (450-600 ms) appeared in the responses to all stimuli. We assume that the "face-specific" components--a designation which is used cautiously considering the limited number of non-face stimuli--do not originate in the temporo-occipital cortical face region, but in limbic structures (amygdala, hippocampus) deep in the temporal lobe or in the gyrus cinguli. In the present study no significant hemispheric differences (T5, T6) in the evoked responses were found (all stimulus categories), but such differences are known to appear with highly schematic face stimuli.

Adult

The role of the 'face-cell' area in the discrimination and recognition of faces by monkeys.

Cortical neurons that are selectively sensitive to faces, parts of faces and particular facial expressions are concentrated in the banks and floor of the superior temporal sulcus in macaque monkeys. Their existence has prompted suggestions that it is damage to such a region in the human brain that leads to prosopagnosia: the inability to recognize faces or to discriminate between faces. This was tested by removing the face-cell area in a group of monkeys. The animals learned to discriminate between pictures of faces or inanimate objects, to select the odd face from a group, to inspect a face then select the matching face from a pair of faces after a variable delay, to discriminate between novel and familiar faces, and to identify specific faces. Removing the face-cell area produced no or little impairment which in the latter case was not specific for faces. In contrast, several prosopagnosic patients were impaired at several of these tasks. The animals were less able than before to discern the angle of regard in pictures of faces, suggesting that this area of the brain may be concerned with the perception of facial expression and bearing, which are important social signals in primates.

Animals

Repetition priming and face processing: priming occurs within the system that responds to the identity of a face.

A familiar stimulus that has recently been recognized will be recognized a second time more quickly and more accurately than if it had not been primed by the earlier encounter. This is the phenomenon of "repetition priming". Four experiments on repetition priming of face recognition suggest that repetition priming is a consequence of changes within the system that responds to the familiarity of a stimulus. In Experiment 1, classifying familiar faces by occupation facilitated subsequent responses to the same faces in a familiarity decision task (Is this face familiar or unfamiliar?) but not in an expression decision task (Is this face smiling or unsmiling?) or a sex decision task (Is this face male or female?). In Experiment 2, familiar faces showed repetition priming in a familiarity decision task, regardless of whether a familiarity judgment or an expression judgment had been required when the faces were first encountered. Expression decisions to familiar faces again failed to show repetition priming. In Experiment 3, familiar faces showed repetition priming in a familiarity decision task, regardless of whether a familiarity judgment or a sex judgment had been asked for when the faces were first encountered. Sex decisions to familiar faces again failed to show repetition priming. In Experiment 4, familiarity decisions continued to show repetition priming when a brief presentation time with encouragement to respond while the face was displayed reduced response latencies to speeds comparable to those for sex and expression judgments in Experiments 1 to 3. The results are problematic for theories that propose that repetition priming is mediated by episodic records of previous acts of stimulus encoding.

Adult

Young and old faces in young and old heads: the factor of age in face recognition.

Research on aging and face recognition has shown age-related differences that are reflected most clearly in false-alarm errors. Elderly subjects exceed young adults in false recognitions that new faces are "old." To determine if this difference between young and elderly subjects might differ for young versus elderly faces, an experiment was conducted in which half of the young and elderly subjects studied and recognized young and middle-aged faces, and the remainder studied and recognized middle-aged and elderly faces. Replicating prior research, age-related deficits in recognition accuracy (d') were reduced with older faces, and this effect generalized from measures of face recognition to measures of face-picture recognition. However, the age-related increase in false recognitions of faces was not affected by face age.

Adult

Identification of familiar and unfamiliar faces from internal and external features: some implications for theories of face recognition.

Three experiments are reported in which recognition of faces from whole faces or internal or external features was compared. In the first experiment, where the faces were of famous people, an advantage was found for identification from internal features. In the second experiment involving unfamiliar faces, however, no difference was found in recognition rates when subjects were given the internal or the external features. In a third experiment famous faces were presented and mixed with other famous faces for a recognition test. As in experiment 1, better recognition occurred from internals as compared with external features. It is argued that the internal representation for familiar faces may be qualitatively different from that for face seen just once. In particular some advantage in feature saliency may accrue to the internal or 'expressive' features of familiar faces. The implications of these results are considered in relation to general theories of face perception and recognition.

Discrimination Learning

Asymmetries in face perception: component processes, face specificity and expertise effects.

Three experiments were carried out to analyze the component processes contributing to observed asymmetries in face perception, to determine whether these asymmetries occur for complex visuospatial stimuli other than human faces, and to investigate the effects of expertise on the asymmetries. Two component processes contributed to the observed asymmetries: perceptual bias (PB) in the observer and face asymmetries (FA). There was no PB effect for complex visuospatial stimuli other than human faces (landscapes, abstract paintings and animal faces). Expertise effects were investigated by examining the judgments of Chinese and Caucasian subjects for own-race and other-race faces. A PB was found for both Caucasian and Chinese faces, but the size of the effect was not related unequivocally to expertise. Caucasian subjects showed a PB for own-race faces only, but Chinese subjects showed a PB for both Chinese and Caucasian faces. There was no FA effect for Chinese faces, even when the composites were perceived as more dissimilar than the Caucasian composites, for which there was an FA effect. The implications of these results for the theoretical interpretation of perceptual asymmetries are discussed.

Analysis of Variance

Non-conscious face recognition in patients with face agnosia.

Four patients with face agnosia, a condition in which there is a failure to recognize previously known faces or faces that ought to have been learned without difficulty, were studied with an experimental paradigm in which both overt (verbal self-report) and covert (electrodermal skin conductance response) probes of recognition were used. The results showed a striking dissociation between the two indices: (1) all 4 patients generated more frequent and significantly larger-amplitude skin conductance responses to familiar faces, as compared to unfamiliar ones. This outcome contrasts with the finding that (2) none of the patients was able to give discriminatory verbal ratings of familiar versus unfamiliar faces. The positive electrodermal discrimination is interpreted as an index of the rich co-activation of records that is produced when familiar facial stimuli successfully trigger the reassembly of previously acquired representations of the physical structure of faces. The results of this co-activation, however, are unavailable to consciousness. This is seen as the consequence of lesion-related disruption of linkages between face records, on the one hand, and non-face records that contain information uniquely and unequivocally apposite to the possessor of a particular face.

Adult

Perception of conspecific faces by budgerigars (Melopsittacus undulatus): I. Natural faces.

Perception of faces by 4 budgerigars (Melopsittacus undulatus), a species of small parrot, was studied with a same-different discrimination task. Reaction times were taken as a measure of the similarity between pairs of faces and analyzed with multidimensional scaling to reveal patterns of similarity among the faces. The perception of natural faces was tested to determine which characteristics were perceptually salient. Color, patterns of markings, darkness of the iris, and size of the pupil corresponded to the observed patterns of similarity among the faces. Differences among budgerigar faces were more salient than differences among zebra finch faces, and budgerigar faces were perceptually distinct from the faces of other avian species. The results from these experiments provide a basis for understanding the ways in which these signals function in the coordination of social behaviors.

Animals

Upside-down faces: a review of the effect of inversion upon face recognition.

Several studies have found that face recognition is disproportionately impaired by stimulus inversion when compated to recognition of other classes of visual stimuli. This effect has been interpreted as evidence that face recognition benefits from a 'special' process which is not engaged by an inverted face. This paper reviews studies of the effect of inversion on face recognition in recognition memory tasks, matching tasks and upon cerebral hemisphere asymmetries. Evidence is drawn from developmental studies and from studies of brain-injured and normal adult subjects. It is concluded that the evidence that inverted faces are processed differently from upright faces is far from compelling, and therefore the effect of inversion provides little or no evidence of a unique process in face recognition. The inversion effect is interpreted in terms of expertise in face processing and the highly homogeneous nature of faces as a stimulus class.

Attention

Visual-field asymmetry in face recognition as a function of face discriminability and interstimulus interval.

Reaction times were measured for recognizing laterally presented faces as a function of two levels of face discriminability and three interstimulus-interval lengths between pairs of successively presented faces. Contrary to many face-recognition studies, no left visual-field/right-hemisphere advantage was observed for the recognition task. Instead, a right visual-field/left-hemisphere advantage occurred at the longest interstimulus interval (500 msec.) on trials on which faces were different and at the shortest interstimulus interval (5 msec.) on trials on which the faces were identical. It appears that visual-field asymmetries in face recognition may vary due to the characteristics of the stimuli and procedures used in face-recognition studies.

Brain

Agreement between face-to-face and telephone-administered versions of the depression section of the NIMH Diagnostic Interview Schedule.

To increase the feasibility of identifying persons with depressive disorders in a large-scale health policy study, we tested the concordance between face-to-face and telephone-administered versions of the depression section of the NIMH Diagnostic Interview Schedule (DIS). This section was administered over the telephone to 230 English-speaking participants of the Los Angeles site of the NIMH Epidemiologic Catchment Area Program (ECA) after their completion of a face-to-face interview (Wave II) with the full DIS. Time lag between interviews was 3 months, on the average. Persons with depressive symptoms were oversampled. Using the face-to-face version as the criterion measure, the sensitivity, specificity, and positive predictive value of the telephone version for identifying the presence or absence of any lifetime unipolar depressive disorder were 71, 89, and 63 percent, respectively; the kappa statistic was 0.57, and agreement was unbiased. The comparable figures for concordance between two face-to-face interviews administered one year apart to the same subjects were 54, 89, and 60 percent and 0.45 (kappa), respectively. Thus, disagreement was due primarily to test-retest unreliability of the DIS rather than the method of administration.

Adolescent

Synthesis and characterization of "face-to-face" porphyrins.

The syntheses of four binary porphyrins, two of which are constrained to a "face-to-face" conformation, and their Co2+ and Cu2+ derivatives are described. Electron spin resonance indicates that the intermetallic separation in the binuclear "face-to-face" porphyrins is about 6.5-6.8 A. Electronic spectra and proton magnetic resonance spectra support the postulated "face-to-face" conformations. A hypothesis that related compounds may serve as multielectron redox catalysts for O2 and N2 is presented.

Cobalt

Analysis of sexual behaviour in France (ACSF). A comparison between two modes of investigation: telephone survey and face-to-face survey. ASCF principal investigators and their associates.

OBJECTIVE: To determine the methodology to be used in a national survey on sexual behaviour in France. DESIGN: To compare two modes of investigation: telephone and face-to-face surveys. METHODS: A questionnaire lasting between 15 and 60 min was administered to 800 people, one-half of whom were interviewed by telephone and the other half face-to-face. RESULTS: We found that questions were more easily answered and answers more coherent in the telephone survey. A face-to-face survey, in contrast, generates a greater diversity in answers and reduces the tendency to give answers relating to behaviours or attitudes that are socially desirable. Results also showed that the acceptation rates were similar in both surveys (66 versus 67%). CONCLUSIONS: Each method has its own advantages and disadvantages; it is therefore difficult to choose one survey method over the other.

Acquired Immunodeficiency Syndrome

Control of gene expression in the temperate coliphage 186. VIII. Control of lysis and lysogeny by a transcriptional switch involving face-to-face promoters.

The lysogenic and early lytic operons of the temperate coliphage 186 are transcribed divergently. Primer extension mapping of the 5' ends of these in vivo transcripts showed that the rightward lytic promoter, pR, and the leftward lysogenic promoter, pL, are arranged face-to-face, with their transcripts overlapping by 60 bases. We examined the control of transcription from pR and pL using galK as a reporter gene. The product of the lysogenic cI gene strongly repressed pR transcription while allowing pL transcription. The product of the lytic apl gene (formerly CP75) strongly repressed pL transcription while allowing pR transcription. Thus, the cI-pR-pL-apl region functioned as a transcriptional switch, determining whether transcription was lytic or lysogenic. Also, the cI gene product was able to stimulate pL, possibly by alleviating an inhibition of pL transcription caused by convergent transcription from pR. Other consequences of the face-to-face promoter arrangement are discussed.

Base Sequence

Implementation of a Face-To-Face Vs Virtual Peer-Integrated Collaborative Care Intervention for Mental Health Treatment of Physical Trauma Survivors: A Qualitative Study of Lessons from the COVID-19 Pandemic.

OBJECTIVE: We assessed the impact of the COVID-19 pandemic on the implementation of a peer-integrated enhancement of integrated clinical care intervention to address the mental health needs of 450 patients undergoing treatment for a physical injury. METHODS: Qualitative data were collected by 7 clinician investigators of a randomized controlled trial acting as participant observers in a trauma care setting of a major U.S. metropolitan hospital and analyzed in collaboration with an external mixed methods specialist. RESULTS: The pandemic created or exacerbated several implementation barriers, including increased risk of infection, homelessness, hospitalizations and comorbid conditions such as fentanyl overdoses that increased demand on emergency department and Trauma Center services, imposition of safety measures to reduce risk of infection in clinical settings, transition from face-to-face to virtual interactions with study patients, shortages of specialty mental health providers, suspension of recruitment of patients into the study, scheduling calls with patients, and an increased workload for the study clinical interventionists. Peer specialists perceived the transition to virtual interactions with patients reduced their effectiveness; however, this was not reflected in assessments of patient satisfaction with services received and may have inadvertently increased adoption by Trauma Center staff. Reduction in reach of the intervention to target population was temporary. CONCLUSIONS: The COVID-19 pandemic exacerbated existing barriers and created new barriers to successfully implementing evidence-based practices in trauma care settings, resulting in an attenuation of their effectiveness. However, the shift from face-to-face to virtual services delivery may have actually led to improved implementation outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03569878. Registered June 15, 2018.

Humans